Question

A van is moving with a speed of $72$ $kmph$ on a level road, where the coefficient of friction between tyres and road is $0.5$. The minimum radius of curvature, the road must have, for safe driving of van, is ($g=10m/s^2$)

• A. $80$ $m$
• B. $40$ $m$
• C. $20$ $m$
• D. $4$ $m$

Answer 1

The correct option is A $80$ $m$

Equating frictional force with centripetal forces,
Centripetal force = Frictional force
$\frac{m{v}^2}{r}=\mu mg$
$\therefore r=\frac{v^2}{\mu g}$
$\therefore r=\frac{{20}^2}{0.5\times 10}$
$\therefore r=80m$